Add process to test RPC

[leopoldsedev]

We should add a process that automatically evaluates all RPC calls.

[eikendev]

Can we use the grading callbacks for this?

[leopoldsedev]

Yes, that would have been the plan

[eikendev]

Can we close this issue?

[abertschi]

What this issue includes: Add verification code on the server side to ensure proper transmission of data. Also cover invalid input on client side.